Printed electronics is a novel recently developed electronics production method. It is a relatively low cost production method allowing flexible placement of passive and active electronic components including resistor, capacitors, inductors and electrical current conductors or simply conductors. Different materials in paste form are used to vary properties such as for example resistance, of the printed conductors and printed components.
One of the primary printing methods for producing conductive patterns on different types of substrates, particularly for features larger than about 100 microns, is screen printing. In screen printing a paste is squeezed through a stencil bearing the desired pattern. When conductive patterns are printed the paste can contain metal particles, such as silver and copper particles or organic conductive materials. Such pastes are usually applied to a substrate to form a patterned layer. The patterned layer then can be dried and transferred to another carrier or fired to remove the organic and inorganic solvents. Some of the difficulties encountered by screen printing include a poor ability to form high-aspect ratio patterns and in particular conductor lines. To get a desired cross section the conductors are increased in their width. Reduction of width of a printed conductor could enhance the density of the electronic circuits packaging, it also increases the conductor resistance and limits current carrying capability in fine conductors.